If you are like me and you store all your code on a server, you will have likely learned about trusting a network share using CasPol.exe. However, when moving from Visual Studio 2008 (.NET Framework 2.0/3.0/3.5) over to Visual Studio 2010 (.NET Framework 4.0), you may find yourself scratching your head.
If you are used to using the Visual Studio Command Prompt to quickly get to CasPol, you may find that some of your projects will not seem to respect your new FullTrust settings. The reason is that, unless you are carefully paying attention, the Visual Studio Command Prompt defaults to adding the .NET Framework 4.0 folder to its path. If your project is still running under .NET Framework 2.0/3.0/3.5, it will require setting CasPol for those versions as well. Just a note, I have also personally had more success with using 1 as a code group instead of 1.2.
To trust a network share for all versions of the .NET Framework, simply call CasPol for each version using the full path as below:
C:\Windows\Microsoft.NET\Framework\v2.0.50727\CasPol -m -ag 1 -url file://YourSharePath\* FullTrust C:\Windows\Microsoft.NET\Framework\v4.0.30319\CasPol -m -ag 1 -url file://YourSharePath\* FullTrust